This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Cytosine methylation (http://www.ks.uiuc.edu/Research/methylation/) is a chemical modification on DNA, which involves replacing a hydrogen atom by a methyl group at the 5'position in cytosine. Methylation of DNA is one of the most important mechanisms in epigenetics. Without changing the sequence of DNA, methylation can alter the expression levels of genes [1]. The physical mechanism underlying methylation is presently under intense study, yet current measurement methods for methylation profiles are still lacking. Previous experiments suggest that methylation can affect DNA properties by changing its structure or its dynamics [2, 3].